1. Field of the Invention
The subject invention relates to photographic film handling equipment and, more specifically, to optical image printers, cameras, projectors, film magazines, including electrically powered film magazines, easy threading film projectors and cameras, and film advancing mechanism, including intermittent film advancing devices and film registration equipment.
2. Prior Art
Optical image printers and their uses are well known, as may, for instance, be seen from Fielding, THE TECHNIQUE OF SPECIAL EFFECTS CINEMATOGRAPHY (Fletcher & Son Ltd., Revised 3rd. ed. 1974) pp. 150-272.
While such equipment has been developed to a high degree of perfection, as may also be seen from U.S. Pat. No. 3,637,299, by L. W. Butler et al, issued Jan. 25, 1972, and herewith incorporated by reference herein, and from U.S. Pat. No. 3,682,540, by J. W. Oxberry, issued Aug. 8, 1972, its very high price extending from the 40,000 dollar well into the 100,000 dollar area, as well as its bulkiness, complexities and need for highly skilled operators, has discouraged the use of such equipment on a large scale, and has maintained this facility beyond the reach of the vast majority of educational institutions and the motion picture amateur and experimental fields.
Similarly, while combined camera and projector apparatus have been proposed in the past, as may, for instance, be seen from U.S. Pat. No. 2,950,646, by F. A. Blank, issued Aug. 30, 1960, existing designs and constructions in this area do not lend themselves to any significant acceptance and use of combined camera and projector equipment.
In the photographic film magazine area, the most prevalent prior-art design maintains the drive of the reel or film takeup member separate from, and relatively stationary to, the film magazine. This requires the provision of engageable and disengageable drive shaft equipment, which is relatively costly, vulnerable to careless handling, and otherwise subject to wear. Against this background, the U.S. Pat. No. 3,043,187, by A. Shaffer, issued July 10, 1962, proposes the provision of both the reel drive and its power source in the form of a coil spring in the magazine itself. Placement of the power source within the magazine housing has, however, the disadvantage that the duration of usefulness of a magazine with a given load will inevitably be dependent on the capacity of the internal power source, rather than the length of the film supply. Practical considerations also relegate the reenergization of the internal power source to the occasions at which the magazine is reloaded with film, as may be seen from the latter patent. More recent developments have followed this trend and have put an electrical power source or battery into the film magazine itself, as may, for instance, be seen from the camera Model SX-70, by Polaroid Corporation.
In the case of easy threading camera, projector and other film handling equipment, there exists the design drawback that the shutter or film pulldown mechanism is stationary, while other parts, such as the lens assembly, are movable. This, so far, has impeded the use of convenient threading and cleaning techniques in many high-precision applications (see U.S. Pat. No. 3,137,201, by Uterhart).
The utility of motion picture film feeding mechanisms with film registering facility has been recognized in the past, as may, for instance, be seen from U.S. Pat. No. 2,733,633, by L. R. Wottring, issued Feb. 7, 1956. This type of prior-art motion picture film feeding and registering mechanism employed a pivoted frame structure surrounding the film aperture for lever action on the registration pin. Other prior-art designs limited themselves to a stationary registration pin. Still other prior-art equipment, such as rapid film feeding and registering devices used in gun sight cameras, provided a construction which excluded the use of the mechanism in projector apparatus.